chore(oss): audit the server package and resync the SDK mirrors

Split the 657-line operation service into eor, submit, and verify
modules, add the AGENT_REVOKED and KEY_RETIRED codes the Backend already
emits, and condense every multi-line comment. Mirror Node, Python, and
Go at 2.1.0 with the deep-health 503, non-idempotent retry, rotation
grace, and path-encoding fixes. Document which routes and response
fields the self-hosted server does not provide.

Claude-Session: https://claude.ai/code/session_01Agoc9bRVE9KL7mmWtey9Vq

sdks/python/pyproject.toml

@@ -47,3 +47,6 @@ elydora = ["py.typed"]
 
 [tool.setuptools.dynamic]
 version = {attr = "elydora._version.__version__"}
+
+[tool.mypy]
+platform = "win32"